The present invention relates to hazardous duty garments and, more particularly, to hazardous duty garments having multiple components which can be worn separately or in combination to meet specific hazardous duty applications.
A typical firefighting ensemble comprises a turnout coat and pant, each of which has an outer shell, a moisture barrier located within the outer shell, and a thermal liner. The outer shell typically is constructed of a flame and heat resistant material such as woven aramid and/or polybenzamidazole ("PBI") fibers. Commercially available aramid fibers are NOMEX and KEVLAR (both are trademarks of E. I. Dupont de Nemours & Co., Inc.). The moisture barrier typically includes a membrane layer, which is moisture vapor permeable but is impermeable to liquid moisture and air, bonded to a substrate of a flame and heat resistant material, such as the aramid or PBI material of the outer shell, only lighter in weight. The thermal liner is typically positioned within the moisture barrier in order to prevent it from soaking up liquid moisture flowing through the outer shell from the ambient environment and comprises a needlepunch or batting of an aramid fiber.
Each layer of the ensemble must meet National Fire Protection Association ("N.F.P.A.") standard 1971 ("Protective Clothing for Structural Fire Fighting") which includes standards for heat and flame resistance and tear strength. For example, the outer shell must be able to resist burning, melting, dripping and separation at a temperature of 500.degree. F. for five minutes. The moisture barrier typically is made of expanded polytetraflouroethylene ("PTFE") such as GORE-TEX (a trademark of W. L. Gore & Associates, Inc.). All layers combined must provide a thermal protection performance ("TPP") rating of at least 35.
The moisture barrier and thermal liner are often stitched together to form a unitary component which is removably attached to the outer shell by snaps and/or hook and loop fasteners. While the combined moisture barrier and thermal liner may be removable from the outer shell, this component is not designed to be worn separately apart from the outer shell, because it lacks such items as a front closure mechanism (e.g. a slide fastener), a collar, or an outer layer of material to protect the component from abrasion.
Another type of hazardous duty garment is a wildlands brush fire firefighting garment. Such a garment must meet N.F.P.A. 1977 performance standard, which require an outer shell of heat, flame, abrasion and tear resistant material, but do not require a moisture barrier or a thermal liner because of the relatively open, drier conditions typically encountered in fighting brush fires. A third type of garment currently in service is an emergency medical service ("EMS") jacket worn, for example, by ambulance teams. Such jackets must meet N.F.P.A. 1999 performance standard for protection against blood borne pathogens. Accordingly, an EMS garment must, for example, have a storm flap covering the front closure and include a moisture barrier.
If a fire department is to have the capability of responding to all of the emergency situations set forth above, it must have on hand a complete inventory of all such garments. For example, it is not desirable to use the conventional turnout ensemble for wildlands brush fire duty, because the thermal liner and moisture barrier would add unnecessarily to the weight and heat retention of the garment, thereby imposing additional stress upon the wearer. Similarly, it is not desirable to wear a wildlands brush fire garment for EMS duty since it does not provide adequate protection against blood borne pathogens.
A disadvantage with having all types of hazardous duty garments in inventory lies in the expense and space required to purchase, maintain and store all three of such garments. Accordingly, there is a need for a hazardous duty garment which is configurable to accommodate more than one hazardous duty application.